In batteries as electrochemical devices, in recent years, much attention has been paid to storage systems to be used for small-size and high energy density applications, for example, information-related apparatus, communication apparatus, that is, personal computer, video cameras, digital cameras, portable telephones, and smartphones, and storage systems for large-size power, for example, for electric vehicles, hybrid vehicles, fuel cell vehicle auxiliary power, and electric power storages. One example of candidate of the battery includes a nonaqueous electrolyte battery such as a lithium ion battery, a lithium battery, a lithium ion capacitor, and the like.
When a battery is a lithium ion battery, when a lithium cation is introduced into a negative electrode at the time of initial charging, the negative electrode and the lithium cation, or the negative electrode and an electrolyte solvent are reacted with each other to form a coating including lithium carbonate and lithium oxide as a main component on the surface of the negative electrode. The coating on the electrode surface is called Solid Electrolyte Interface (SEI), and the property thereof give a large influence on the battery characteristics.
In order to improve battery characteristics including durability, it is important to form a stable SEI having high lithium ion conductivity and low electronic conductivity. An attempt to form excellent SEI is actively carried out by adding a small amount (usually 0.01 mass % or more and 10 mass % or less) of a compound called an additive agent into an electrolyte.
For example, Patent Document 1 uses vinylene carbonate, Patent Document 2 uses unsaturated cyclic sulfonic acid, Patent Document 3 uses carbon dioxide, and Patent Document 4 uses lithium tetrafluorooxalatophosphate, respectively, as an additive agent for forming effective SEI.    Patent Document 1: Japanese Patent No. 3573521    Patent Document 2: Japanese Unexamined Patent Application, Publication No. 2002-329528    Patent Document 3: Japanese Unexamined Patent Application, Publication No. H7-176323    Patent Document 4: Japanese Patent No. 3722685